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Voracious, venomous and hella leggy, house centipedes are masterful predators with a knack for fancy footwork. But not all their legs are made for walking, they put some to work in other surprising ways.

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Recognizable for their striking (some might say, repulsive) starburst-like shape, house centipedes have far fewer than the 100 legs their name suggests. They’re born with a modest eight, a count that grows to 30 as they reach adulthood.

If 30 legs sound like more than one critter really needs – perhaps it is. Over the last 450 million years or so, when centipedes split off from other arthropods, evolution has turned some of those walking limbs into other useful and versatile tools.

When it hunts, for example, the house centipede uses its legs as a rope to restrain prey in a tactic called “lassoing.” The tip of each leg is so finely segmented and flexible that it can coil around its victim to prevent escape.

The centipede’s venom-injecting fangs, called forciples, are also modified legs. Though shorter and thicker than the walking limbs, they are multi-jointed , which makes them far more dexterous than the fangs of insects and spiders, which hinge in only one plane.

Because of this dexterity, the centipede’s forciples not only inject venom, but also hold prey in place while the centipede feeds. Then they take a turn as a grooming tool. The centipede passes its legs through the forciples to clean and lubricate their sensory hairs.

Scientists have long noticed that because of their length and the fact that the centipede holds them aloft when it walks, these back legs give the appearance of a second pair antennae. The house centipede looks like it has two heads.

In evolution, when an animal imitates itself, it’s called automimicry. Automimicry occurs in some fish, birds and butterflies, and usually serves to divert predators.

New research suggests that’s not the whole story with the house centipede. Electron microscopy conducted on the centipede’s legs has revealed as many sensory hairs, or sensilla, on them as on the antennae.

The presence of so many sensory hairs suggest the centipede’s long back legs are not merely dummies used in a defensive ploy, but serve a special function, possibly in mate selection. During courtship, both the male and female house centipede slowly raise and lower their antennae and back legs, followed by mutual tapping and probing.

--- Are house centipedes dangerous?

Though they do have venom, house centipedes don’t typically bite humans.

--- Where do house centipedes live?

House centipedes live anywhere where the humidity hovers around 90 percent. That means the moist places in the house: garages, bathrooms, basements. Sometimes their presence can indicate of a leaky roof or pipe.

--- Do house centipedes have 100 legs?

No. An adult house centipede has 30. Only one group of centipedes, called the soil centipedes, actually have a hundred legs or more.